The present invention relates generally to the field of communication systems, and more particularly, to systems implementing packet data technologies.
A network architecture for routing control (signaling) information and bearer traffic in a packet network system is shown in the functional block diagram of FIG. 1. In the diagram, the flow of control information is shown using dashed lines, the flow of bearer traffic is shown using thin solid lines and the flow of control information and bearer traffic is shown using thick solid lines. When a subscriber is in a first coverage area (A1) and requests a service either manually or automatically on powering up his or her wireless communication device, such as mobile station (MS) 108, certain information about that subscriber is communicated to infrastructure equipment. In particular, the information is communicated to a First Serving Node 104 via a First Access Network Controller (ANC) 106. This process is generally referred to as establishing a connection. After a connection is established and while the MS 108 remains in the first coverage area, control and bearer traffic transmitted from the MS 108 is routed through the First ANC 106 to the First Serving Node 104. The First Serving Node 104 processes the control information and forwards the bearer traffic to an appropriate Gateway Node 102 for processing. Control and bearer traffic entering the system through an appropriate Gateway Node 102 is transmitted to the MS 108 through the First Serving Node 104 and First ANC 106.
As the MS 108 roams from the first coverage area into a new coverage area (A2) serviced by a new serving node, Second Serving Node 110, all control and bearer traffic from and to the MS 108 for the existing connection is routed through the new serving node. However, because the Second Serving Node 110 did not establish the connection, it must obtain information about the MS 108 from the First Serving Node 104 where the connection was established in order to process the signaling information. The node where the connection was established is referred to herein as the anchor node. MS information for a particular connection is maintained at the anchor node to provide simplicity in billing and charging, legal intercept (i.e. wiretapping), Gateway nodes and handover procedures, to name a few. For example, most carriers perform billing and charging functions at the control point (where the connection is established) to minimize complexity and maximize efficiency.
Thus, there is a need for an improved method of routing control information and bearer traffic in a packet network system.